Pumice briquettes are granulated volcanic stone briquettes bonded together by a suitable bonding agent and compressed in a forming press. In one exemplary configuration, the briquettes are generally triangular in shape although they have curved edge surfaces. In recent years pumice briquettes have found considerable commercial acceptance as grease burning elements in gas fired outdoor grills. That is, the briquettes are placed below the grill, and when the grease drips on the briquettes it vaporizes in a manner similar to the effect achieved in a charcoal broiler and serves the same taste enhancing function without the decomposition disadvantage of charcoal briquettes. Heretofore, forming machines for briquettes of this type have been manually unloaded. This is an extremely tiresome, time consuming and expensive function because there are a large number of briquettes formed on each stroke of the forming press.
There have in the past been provided automatic pickers with rubber diaphragms that push construction bricks, much larger and heavier than the pumice briquettes from brick presses. However, these operate with the press charging device from the side of the bricks and are not at all suitable for removing the briquettes or bricks from above.
While vacuum material handling devices have been applied in other material handling areas, they have not, insofar as applicants are aware, been applied to handling briquettes, or even to handling bricks during the unloading operation from the press. The various general utility material handling devices, such as found in the metal working arts, have been found to be completely unacceptable for handling pumice briquettes or bricks because their composition, shape and number in the press present problems not found in any other art.
For this reason it is a primary object of the present invention to provide a brick or briquette unloading apparatus for a forming press that will simultaneously unload a plurality of formed articles from above the lower mold half by raising the articles upwardly and outwardly from the press all in a completely automatic and simple operation, interlocked with the operation of the press itself.